Wafer transport systems configured for use in semiconductor wafer-level processing typically include a stage having a chuck that secures the wafer for processing. Sometimes the stage is stationary, and sometimes it is moveable. Some applications require that the stage move linearly in one, two, or three Cartesian dimensions, with or without rotation. The speed of the stage motion can dictate the throughput of the entire wafer processing platform if a significant amount of the total process time is spent aligning and transporting the wafer.
For applications including optical processing, a moveable optics assembly can be mounted above the wafer surface, thereby minimizing the wafer transport distances required. The primary direction of stage motion is referred to as the “major axis,” and the direction of stage motion perpendicular to the primary direction is referred to as the “minor axis.” The chuck holding the specimen, here a wafer, to be processed is mounted to a major axis stage for movement along the major axis, a minor axis stage for movement along the minor axis, or in a stationary position below the major and minor axes. The major axis stage may support the minor axis stage, or they may be independent of each other.